The need for continuously monitoring a species like hydrogen sulfide and methyl mercaptan in the atmosphere is readily apparent because of the toxic nature of these compounds. It is particularly important in synfuel production and in geothermal energy utilization. Also, hydrogen sulfide is an impurity in synthesis gas which is used in the industrial production of methanol, methane, glycols and other hydrocarbons. Costly catalysts used in petrochemicals are readily "poisoned" unless the hydrogen sulfide level is below one part per million. Presently, hydrogen sulfide in air can be determined by colorimetry, conversion to metal sulfides and subsequent photometry, gas chromatography with flame photometric detectors, and ion-selective electrodes. The problem with all of these techniques is that for low concentration levels, they all require collecting the gas sample of interest over fairly long times followed by capture and concentration of hydrogen sulfide and some chemical preparation. Thus, they cannot achieve truly continuous monitoring.
It is therefore a primary objective of the present invention to provide not only a highly sensitive detection method for hydrogen sulfide and methyl mercaptan which will detect those at very low levels, even as low as one part per billion, but also to allow detection of those in a method which is truly continuous to allow continual monitoring of industrial reactions for the presence of potentially poisoning sulfide.
It is also an object of the present invention to provide not only a continuous, highly sensitive monitoring system for sulfide containing compounds, particularly hydrogen sulfide and methyl mercaptan, but also to provide a new chemical reaction which allows the use of chemiluminescence technology to conduct the detection and determination method of the invention.
An even further objective of the invention is to provide a reaction cell which allows continuous monitoring and reaction for determining chemiluminescently the presence of potentially poisoning sulfide atoms.
The method, means and apparatus for accomplishing each of the above objectives will be apparent from the detailed description of the invention which will follow hereinafter.